JPH0611518B2 - Synthetic resin pipe manufacturing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is mainly for synthesizing corrugated pipes, etc., which are required to have a large diameter and high flatness and pressure resistance, such as electric wire pipes and drain pipes buried in the soil. The present invention relates to a resin pipe manufacturing apparatus, and more specifically, while winding a synthetic resin strip material extruded or extruded from a die in a spiral shape, the side edges of adjacent strip materials in the axial direction of the pipe are The present invention relates to an apparatus for continuously producing a synthetic resin pipe by polymerizing and heat-welding the polymerized portion.

(Prior Art) A conventional method for producing a synthetic resin pipe, for example, as disclosed in JP-A-57-110426, on an arc line equal to the inner diameter of the pipe body to be molded. A plurality of long rolls are arranged at appropriate intervals in the circumferential direction in a state in which their axes are parallel to each other, and these long roll groups are driven and rotated at the same speed in the same direction. It is configured as one rotating body called a mandrel, and the molten resin strip material extruded from the die is attached to the mandrel shaft center on the peripheral surface of the rotating body, that is, the mandrel. There is a method in which, by feeding in from an inclined direction, the strip material is wound around the mandrel circumferential surface into a spiral strip, and the side edge portions of adjacent strip materials are polymerized and heat-welded. As another method, a plurality of long rolls constituting the mandrel are arranged in a posture in which their axes are slightly inclined with respect to the mandrel axis, and the mandrel is a molten strip material extruded from a die. By feeding and feeding the mandrel peripheral surface from a direction at right angles or substantially at right angles to the axial center, while winding the strip material into a spiral strip by the inclination of the axis of the long roll group as described above, There is also one in which the side edges are polymerized and heat welded.

(Problems to be Solved by the Invention) However, in the case of the above-mentioned manufacturing method, the spiral winding action of the synthetic resin strip material is maintained in the molten state immediately after the strip material is extruded from the die. Since it is performed along with the feeding and feeding to the outer peripheral surface of the mandrel, in order to improve the dimensional accuracy and quality in manufacturing, it is necessary to uniformly hold and manage the extrusion melting temperature and the like of the strip material, The manufacturing speed is naturally limited, and in addition, since it is cooled after it is molded into a tube of a predetermined shape, the pressure resistance and flat strength of the manufactured tube are determined by the wall pressure of the tube wall. It is no exaggeration to say that there is almost no added strength in terms of manufacturing. In addition, from the viewpoint of equipment, not only is the mandrel structure complicated, but mandrel of different size must be used for each tube of different diameter. It had a lot of problems that it required a lot of equipment cost, which also reflected in the product cost.

The present invention has been made in view of the above circumstances, and it is possible to efficiently manufacture a synthetic resin pipe excellent in accuracy and quality, and the compressive strength of the same pipe wall thickness is higher than that of the conventional one. A first object is to propose a manufacturing apparatus capable of obtaining an excellent synthetic resin tube, and a second object is to provide a manufacturing apparatus for a synthetic resin tube having a simple structure and having a wide applicability to a pipe diameter. It is in the point of providing.

(Means for Solving Problems) In order to achieve the above object, a synthetic resin pipe manufacturing apparatus according to the present invention comprises a cooling device for cooling a synthetic resin strip material in a molten state, and a cooled synthetic resin product. A delivery device for delivering the strip material in a straight line, and at least two or more forming roller groups for pressing and forming the strip material in an arc shape and in a spiral direction by abutting the strip material, and forming a circular spiral shape. A device for sequentially superimposing side edges of the formed pipe wall on each other for heat welding, and a take-up roller group for supporting the formed pipe body and for guiding the take-out, and the forming roller group should be formed. Arranged along the virtual outer diameter line of the tubular body and sequentially displacing it in the take-up direction of the strip material in an inclined posture along the spiral angle of the synthetic resin strip material forming the tube wall of the pipe body to be molded. Is a synthetic resin pipe manufacturing device The characteristic feature of the present invention is that the position of the forming roller group can be changed and fixed in the direction of changing the outer diameter of the tubular body to be formed.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

In FIGS. 1 to 4, (1) constitutes a pipe wall of the pipe body (P) to be formed in a state along a virtual outer diameter line of the corrugated pipe body (P) made of synthetic resin to be formed. Synthetic resin strip material
(A) a plurality of forming rollers arranged in such a manner that the strip material (A) is gradually displaced in an inclined posture along the spiral angle,
Corresponding to the outer corrugated pipe wall of the corrugated pipe body (P) to be molded, these have the same peripheral shape as the outer peripheral surface shape of the resin strip material (A) having the outward protruding hollow ridges (a). It has a groove (1a), and each is configured to be rotatable at a constant speed through a motor (not shown). (6) is a resin strip material extruded from the die (3), which is cooled by passing it through a cooling device (4) and is molded into a straight line with a predetermined shape.
(A) is a molding roller (1A) located at one end of the molding roller (1) in the axial direction of the molding roller (1) and a pipe at a position slightly displaced in the circumferential direction on the inner side of the molding roller (1A). It is forcibly fed from the tangential direction or approximately tangential direction to the pipe wall of the pipe body (P) to be molded between the roller (2) and the roller (2) oppositely arranged with a gap corresponding to the wall thickness. A delivery device, which is a plurality of pairs of rollers (6A) and (6A) arranged in parallel relative to each other so as to sandwich and transfer the linearly formed resin strip material (A) from above and below. ) Consists of pairs. (5) is the molding roller (1A), one end edge in the axial direction of the tube wall (B) that is pressed and bent in an arc shape and a spiral shape by the (1), and then the molding roll (1A) is paired. A device for superimposing the axial other end edge portion of the strip material (A) fed between the installation roll (2) and the heat-melting the superposed portion while heating and melting the superposed portion, A heating device (7) such as a burner and the roller (2) described above.
It is located on a common center line with the center line, and the center line is positioned so as to be positioned at a right angle or a substantially right angle with respect to the tangent of the overlapping portion between the pipe wall (B) and the strip material (A) to be fed next It is composed of a pressure roller (5A). (8) is a plurality of rows, each of which is arranged in two rows at a central angle of about 120 degrees in the circumferential direction so as to support the heat-welded tube (P) at two locations in the circumferential direction. In the tube take-out guide roller group, each of these rollers (8) is rotatably supported around the inclined axis center in accordance with the feed pitch of the tube wall (B). Thus, each of the forming rollers (1A), (1) group and take-up guide roller (8) group has a fluid pressure cylinder (9) in a direction to change the outer diameter of the pipe body (P) to be formed. The position is changeable and can be fixed.

Next, a corrugated tubular body made of synthetic resin having a tubular wall cross-sectional shape as shown in FIG.
The method for continuously producing (P) is listed below in the order of steps.

(1) A linear synthetic resin strip material (A) extruded from a die (3) and cooled through a cooling device (4) and formed into a predetermined shape is passed through the delivery device (6). Then, it is forcibly fed from the tangential direction or the substantially tangential direction between the starting end forming roll (1A) and the roller (2) which also serves as the pressure bonding roller base.

(2) The strip material (A) fed between the two rollers (1A) and (2) as described above is abutted against the peripheral surface of the starting end forming roller (1A) and circles upward. It is pressed and bent into an arc shape and a spiral shape.

(3) Next, it is pressed against the forming rollers (1) adjacent to each other in the circumferential direction and similarly press-bent formed, and such press-bend forming is sequentially performed on all the forming rollers (1). As a result, a circular spiral tube wall (B) is formed when viewed in the tube axis direction.

(4) The circular spiral tube wall (B) is the starting end forming roller described above.
Since it is advancing by 1 pitch with respect to (1A), it is fed into one side edge portion in the axial direction thereof, and then between the forming roller (1A) and the roller (2) opposite thereto. The edge of the strip material (A) on the other side in the axial direction is superposed on the inside and outside.

(5) The pressure-bonding roller (5) and the roller while locally heating and melting the overlapping end portion with a heating device (7) such as a burner.
(2) By pressing each other via and, the spiral tube wall
(B) and the strip material (A) are integrated by heat welding. (6) The corrugated pipe body (P) is continuously manufactured by repeating the above operation, and the manufactured corrugated pipe body (P) is supported by the take-up guide roller (8) group and has a constant pitch. It will be sent out in sequence.

The above is the manufacturing process for a corrugated pipe body (P) of one diameter size. When manufacturing a corrugated pipe body (P) of a different diameter, the fluid pressure cylinder must be prepared in advance before the start of manufacturing.
The positions of the forming rollers (1A), the group (1) and the take-up guide roller (8) group are changed and set via (9).

The cross-sectional shape of the molding target corrugated tube (P) may be any shape other than the above example, and may be a straight tube instead of the corrugated tube.

Further, the position changing means of each roller (1A), (1) group and (8) is
Any mechanism other than the cylinder may be used.

(Effects of the Invention) As is apparent from the details described above, according to the synthetic resin pipe manufacturing apparatus of the present invention, the synthetic resin strip material in a molten state is not wound, but is extruded and cooled. Since the linear strip material is forcibly abutted against the forming roller in the cold and is press-bently formed, each strip material constituting the manufactured pipe wall is to be restored to the outside. Residual stress is generated. Therefore, it is possible to manufacture a tube having excellent flatness and pressure resistance as compared with a tube manufactured to have the same thickness and the same shape by the conventional method. Moreover, since it is manufactured by cold working, it is possible to obtain a tubular body excellent in dimensional accuracy and quality while improving the production efficiency regardless of the melting temperature and the like during extrusion.

In addition, when using the device of the present invention, not only is the structure simpler than that of the mandrel type used in the above-mentioned conventional method, but also the pipe diameter size is different due to the addition of a simple structure such as changing the position of the forming roller group. It is possible to manufacture multiple types of pipes, and it is not necessary to use a device equipped with a separate mandrel for each pipe diameter size, reducing the equipment cost required for manufacturing pipes of various pipe diameter sizes, and eventually the product cost. It came to have a great effect on.

[Brief description of drawings]

1 to 4 show an embodiment of an apparatus for producing a synthetic resin pipe according to the present invention. FIG. 1 is a schematic perspective view of a main part, FIG. 2 is a schematic front view of the whole, and FIG. 3 is a forming roller. FIG. 4 is an enlarged plan view of the main part showing the arrangement of the groups, FIG. 4 is a side view of the main part, and FIG. 5 is an enlarged cross-sectional view of the pipe wall of the corrugated pipe body. (1A), (1) …… Molding roller, (2) …… Roller, (3) …… Die, (4) …… Cooling device, (5) …… Heat welding device, (5A) …… Crimping roller , (6) …… Article feeding device, (7) …… Heating device,
(8) …… Take-off guide roller, (9) …… Fluid pressure cylinder,
(P) …… Corrugated pipe body, (A) …… Resin strip material.

Claims (3)

[Claims] 1. A cooling device (4) for cooling a molten synthetic resin strip material (A), and a delivery device (6) for linearly delivering the cooled synthetic resin strip material (A). At least two or more forming rollers (1) for pressing and forming the strip material (A) in an arc shape and in a spiral direction, and side edges of the pipe wall (B) formed in a circular shape in the spiral direction in order. An apparatus (5) for polymerizing and heat welding, and a group of take-up rollers (8) for supporting and guiding the molded tube (P) and for guiding the take-up, and the molding roller.
(1) The group is in a state along the virtual outer diameter line of the pipe body (P) to be molded,
In addition, the synthetic resin strip material (A) that constitutes the tube wall of the pipe body (P) to be molded is arranged by sequentially displacing it in the take-up direction of the strip material (A) in an inclined posture along the spiral angle of the strip material (A). A resin pipe manufacturing apparatus, characterized in that the position of the forming roller (1) group is configured to be positionally changeable and fixed in a direction in which the outer diameter of the pipe body (P) to be formed is changed. Manufacturing equipment for synthetic resin pipes. 2. The synthetic resin pipe manufacturing apparatus according to claim 1, wherein the position changing means of the molding roller (1) group uses a fluid pressure cylinder (9). 3. The delivery device (6) comprises a plurality of sets of rollers for sandwiching and transferring a synthetic resin strip material (A) extruded from a die (3) and cooled through a cooling device (4). The synthetic resin pipe manufacturing apparatus according to claim 1, which comprises (6A) and (6A).